As it turns out, the Cardinals had no idea Swope's medical concerns would keep him out of offseason practices as he awaits doctor's clearance.

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"We were very, very, very surprised about it," coach Bruce Arians told NFL.com's Ian Rapoport on Friday. "I'm not sure what he can do, I'm not sure what the doctors are going to do at this point. I hope ... because the kid is a great talent, and it would be a shame. But having Austin Collie last year, go through this same thing, it's scary."

Asked which rookies have been impressive, Arians said, "I like them all. ... Only guy I'm worried about is Swope with his head."

The Cardinals can't count on Swope returning to the field for training camp if he's yet to gain medical clearance six months after his last game for Texas A&M. In the meantime, he joins Jahvid Best of the Detroit Lions in concussion purgatory.